I cheated on my Pottermore sorting quiz just like everyone else. I read the questions wondering - not what my preference was - but what answer would get me bragging rights for the house I wanted. Where wit beyond measure is man's greatest treasure, and you have to be smart enough to answer riddles to get into the common room, I was more proud of the day I was sorted in Ravenclaw than the day I graduated college. Or high school. Combined.
The funny thing about the sorting is that (without geeking out too hardcore here) the house you want is the house you get sorted into. Harry doesn't want Slytherin; he gets Gryffindor.